Tobacco smoke filter



June 27, 1967 J. 1 AZORLOSA 3,327,715

TOBACCO SMOKE FILTER Filed Oct. 2, 1964 am o 96 P?) 4 3 Fig l.

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Julian L. Azorioso INVENTOR BY y / ATTORNEYS United States Patent3,327,715 TOBACCO SMOKE FILTER Julian L. Azorlosa, Easton, Pa., assignorto General Aniline & Film Corporation, New York, N.Y., a corporation ofDelaware Filed Oct. 2, 1964, Ser. No. 401,025 8 Claims. (Cl. 131-101)The present invention relates, in general, to minimizing certainundesirable effects obtained from the combustion of tobacco and, inparticular, to improved tobacco products.

With the discovery that certain residues from tobacco smoking werephysiologically objectionable to the human body and produced or weredirectly responsible for lung cancers, many attempts have been made toremove such residues during processing of the tobacco or to remove thesame during the tobacco combustion process. The latter attempt hasprobably received the most attention since it is more economical andsimpler to execute. The general public is probably more familiar withthe end product of the latter treatment under the popular term filtercigarettes. The term filter cigarette is generally applied to thoseproducts which have at one end thereof a filtering material containingan adsorbent capable of adsorbing tars and irritants, through which thesmoke is passed prior to inhalation by the smoker thereof. The filter,of course, should not substantially interfere with the pleasurable actof smoking from the standpoint of flavor and, physically, should notdeter the passage of air through the filter while simultaneouslyremoving tars and irritants from tobacco smoke.

Accordingly, it is an object of this invention to provide an improvedfiltering material for removing tars and irritants from tobacco smoke.

Another object of this invention resides in the provision of an improvedfiltering medium for filter cigarettes which is capable of adsorbingtars and irritants yet does not interfere with the passage of airthrough the filter or substantially detract from the flavor of the smoketo the user thereof.

Other objects, features and advantages of the invention will becomefurther apparent hereinafter from the more detailed description of theinvention which follows.

In accordance with the aforesaid objects of the invention methods andproducts have been devised comprising a tobacco product and as afiltering medium therefor 21 filter comprising essentially insolublepolymers of N- vinyl-alpha-pyrrolidones.

As used herein the terms insoluble polymers of N-vinyl-alpha-pyrrolidones and insoluble polyvinyl pyrrolidone areintended to include products which are insolu ble in water, strongmineral acids, caustic solutions and common organic solvents, and todistinguish such products from the soluble polymeric materials based onN- vinyl-alpha-pyrrolidone known in the art as represented by US.Patents Nos. 2,265,450, and 2,335,454. Such insoluble polymers of thetype referred to above can be produced in accordance with the teachingsof F. Grosser, as set forth in US. Patent 2,938,017, patented May 24,1960.

The insoluble polymers of vinyl lactams are preferably employed in theform of a filter element for removing the tars and gums from tobaccosmoke in cigarettes, pipes or cigars.

The single sheet of drawings illustrates various preferred embodimentsof such filter elements. In the drawings FIGURES 1 and 2 illustratefilter-tip cigarettes; while FIGURE 3 illustrates a holder forcigarettes or cigar; and FIGURE 4 illustrates a pipe.

As illustrated in FIGURE 1, a cigarette designated as 1 may be providedwith a cylindrical filter element comprising a cylindrical wall, 2,filled with granules of insoluble polyvinyl pyrrolidone 3; and held inplace by cotton or other fibrous packing 4. Another form of cigarette isillustrated in FIGURE 2 wherein 11 designates a cigarette; while 12designates the cylindrical wall of a filter element filled with amixture of fibers 13 of cotton, cellulose acetate or other fibrousmaterial and granules of insoluble polyvinyl pyrrolidone 14.

It is also possible to employ separate disposable filter elementsparticularly when using a cigarette or cigar holder. As shown in FIGURE3 a cigarette or cigar 21 may be held in metal or plastic hollow holder22, in the central opening of which there is placed a tube of paper,plastic, metal foil or the like 23 which is filled with granules 24 ofinsoluble polyvinyl pyrrolidone retained therein by plugs 25 of cottonor other suitable fibrous material.

Such disposable filters can also be employed in pipes by providing anenlarged chamber in the end of the pipe stem 31 as illustrated in FIGURE4, in which there is placed a removable cylindrical element 32 of paper,metal foil, plastic or the like which is filled with granules 33 ofinsoluble polyvinyl pyrrolidone held in place therein by plugs 35 ofsuitable fibrous material.

While I particularly prefer the insoluble polymersN-vinyl-alpha-pyrrolidone, insoluble polymers of other N-vinyl lactams,can be used to obtain similar results.

Preferred N-vinyl lactams which find immediate and practical utility inthe practice of the present invention are those characterized by theformula:

(OHRM CH=CH2 wherein R represents a member of the group consisting ofhydrogen and alkyl groups containing from 1 to 4 carbon atoms and nrepresents a whole positive integer of from 2 through 4.

While the insoluble polymers of polyvinyl pyrrolidone and its hemologueswhich are illustrated by the above formula are particularly preferred, anumber of other lactams can readily be vinylated in the manner describedin US. Patent 2,317,084 and the insoluble polymers thereof may beemployed in practicing the above invention. Broadly, the N-vinyllactamsWhOSE insoluble polymers may be employed in practicing the presentinvention, may be illustrated by the following general formula:

wherein R and R represent hydrogen, alkyl or aryl and n and n representan integer from 0 to 5 inclusive but only one of the n and n values maybe 0. Y represents O *S 2 2-pyrrolidone, 4-acryl-2-pyrrolidone,-ethyl-2-pyrrolidone, 3-methyl-2-pyrrolidone, 4-methyl-2-pyr-rolidone,5- methyl-Z-pyrrolidone, 3,3,5-trimethyl-2-pyrrolidone; 2- pi-peridone,5,5-diethyl-2-piperidone, 5,6-di-methyl-2-pi-peridone,4-ethyl-2-piperidone, 6-ethyl-2-piperid-one, 6-ethyl-B-methyI-Z-piperidone, 3-methyl-2-piperidone, 4-methyl-2- piperidone,S-methyl-Z-piperidone, 6-methyl-2-piperidone; 2-caprolactam,3,6-dimethyl-2-caprolactam, 4,6-dimethyl- 2-caprolactam,4,7-dimethyl-2-caprolactam, 7,7-diethyl-2- caprolactam,S-ethyl-Z-caprolactam, 5-ethyl-2caprolactam, 6-ethyl-2-caprolactam,7-ethyl-2-caprolactam, 4- ethyl-6-methyl-2-caprolactam,6-ethyl-4-methyl-2-caprolactam, 3-methyl-2-caprolactam,4-methyl-2-caprolactam, 5-methyl-2-caprolactam, 6-methyl-2-caprolactam;2-oxazinidinone (e.g. U.S.P. 2,905,669 and U.S.P. 3,097,087),5-ethyl-2-oxazinidinone, 5-pl1enyl-2-oxazinidinone, 4,5dimethyl 2-oxazinidinone, 5,5-dimethyl-Z-oxazinidinone,2,S-diphenyl-Z-oxazinidinone, 2-phenyl-4-oxothiazolidone,2,2-diphenyl-4oxathiazolidone, 2,2 dimethyl-4-oxothiazolidone;2-oxazolidinone (deriv. in U.S.P. 2,905,690 and U.S.P. 2,891,058),5-methyl-2-oxazolidinone, 4-methyl-2- oxazolidinone,5-ethyl-2-oxazolidinone, 4,5-dimethyl-2- oxazolidinone,2-phenyl-2-oxazolidinone, 5-butyl-2-oxazolidinone,5-propyl-=2-oxazolidinone, 4,5-diethyl-2-oxazolidinone; 3-morpholinonedisclosed in U.S.P. 2,987,509 e.g. 5-methyl-3-morpholinone,5-ethyl-3-morpholinone) and the E-1353 products namely3,5-dirnethyl-3anorpholinone) and the 2 alkyl and 6-alkyl derivatives;2-piperazinone (e.g. JACS 62, 1202 (1940), the 3,3-dimethyl-2-ketopiperazine, 3-methyl-2-ketopiperazine; 4-thiazolidone (e.g. JACS,76, 578 (1954), 2-methyl-4-thiazolidinone; 2-phenyl-4-thiazolidinone;2-phenyl-4-thiazolidinone dioxide; Z-thiazolidone (J. Chem. Soc., 1949,2367); 3-thiamorpholinone; 2-pyrimidone (e.g. .T. Chem.'Soc. 1959, 525);Z-imidazolidones (e.g. Ann., 232, 1222 (1885), N,N-ethylenethioureas(e.g. J. Biol. Chem, 163, 761 (1946); tetrahydro-ZH, 1,3)-oxazin-3-ones(e.g. U.S.P. 2,940,971), and the like.

The aforesaid insoluble polymers of the above-men tioned N-vinyl lactamscan be readily prepared by heating the same at elevated temperatures inthe presence of a catalyst such as alkali metals, alkaline earth metalsas well as the oxides, hydroxides and alkoxides of these metals.

Another group of catalysts which have been found effective in producinginsoluble polymers of N-vinyl lactarns include the hydrides andborohydrides of the alkali metals. Representative alkali metal hydridesand borohydrides which have been tested and found efiective includesodium borohydride, potassium borohydride and sodium hydride. Otheralkali metal hydrides and borohydrides which can also be employedinclude lithium hydride, lithium borohydride, cesium hydride, cesiumborohydride, rubidium hydride and rubidium borohydride. If desired,mixtures of alkali metal hydrides and/or alkali metal borohydrides canbe employed as catalysts for the polymerization.

Similar results can be obtained by applying a small amount of insolublepolyvinyl pyrrolidone to tobacco, preferably in the tobacco portion usedin the filter end of the cigarette or cigar, either in the leaf at anystage of its processing before or after it is ground or cut.

The following examples will serve to illustrate the practice of theinvention.

Example 1 A one and one-half inch length of ten millimeter diameterglass tubing was loosely packed to a height of one-half inch withpowdered cellulose acetate, a conventional cigarette filter material.Small adsorbent cotton plugs were used to retain the material in thetube. A Phillip Morris cigarette was then smoked as completely aspossible through the filter. The filter material, i.e. celluloseacetate, was then removed and dissolved in a 1:4 combination of ethanoland ethylene dichloride. The res-ulting solution was then measured forlight absorption at 400 millimicrons on a Hardy Spectrophotometer. Theabsorption readings are indicative of the test materials efiiciency fortrapping tars and other irritants in the tobacco smoke. The free drawingproperties of the filter for the life of the cigarette were also noted.

Example 2 The same procedure as set forth in Example 1 was em ployedexcept that a water soluble polyvinyl pyrrolidone, having a Fi'kentscherK value of 30, of -200 mesh, was employed to prepare the filter.

Example 3 The same procedure as set forth in Example 1 was employedexcept that a 50:50 mixture of the filter materials of Examples 1 and 2was employed to prepare the filter.

Example 4 The same procedure as set forth in Example 1 was employedexcept that an insoluble polyvinyl pyrrolidone of 100-200 mesh producedas described in Example 1 of U.S. Patent 2,938,017 was employed toprepare the filter.

The data and results obtained are summarized in the following Table 1:

TABLE 1 Example Absorption at 400 m Remarks 1 0.83 Free drawing filter.

0.28 Filter clogged after few putts. 0. 8 o. 0.96 Free drawing filter.

Equal parts by weight of cellulose acetate fibers of 5 denier perfilament and powdered insoluble polyvinyl pyrrolidone of 100-200 meshand produced as described in Example 1, U.S. Patent 2,938,017, wereintimately mixed by rolling in a one'half filled jar for several hours.They were then made up into cigarettes on a cigarette making machine andcut into plugs having a length of These filter plugs were attached tothe end of regular cigarettes (non-filter) by an outer wrapping ofpressure sensitive adhesive tape. Similar filter plugs were made up ofthe same cellulose acetate fibers unmixed with the insolublepolyvinylpyrrolidone. These plugs were also attached as filters to thesame type cigarettes in the similar manner. Both cigarettes were smokedto within about A" of the filter and it was noted that the smoke fromthose cigarettes having a filter containing the insolublepolyvinylpyrrolidone was much milder than that from the cigarette havingonly a cellulose acetate filter.

Example 6 In a manner similar to that described in Example 5, equalparts by weight of cigarette tobacco and powdered 100-200 mesh)insoluble polyvinylpyrrolidone, produced in the manner described inExample 1 of U.S. Patent 2,938,017, were mixed and made-up into filterplugs which were attached to non-filter cigarettes by an outer wrappingof pressure sensitive adhesive tape. Similar plugs were also made-up ofthe same cigarette tobacco and attached to cigarettes from the samebatch. Both types of cigarettes were smoked and it was noted that thesmoke from the cigarettes in which the filter contained insolublepolyvinylpyrrolidone Was much milder than that from the othercigarettes.

'The amount of insoluble polyvinyl pyrrolidone employed to effect thedesired decrease in irritational properties of the tobacco or the smoketherefrom should be a minimum amount because of the relatively high costof insoluble polyvinyl pyrrolidone. Such amount may vary with varioustypes of tobacco and With the method in which the insoluble polyvinylpyrrolidone is incorporated in the tobacco. The optimum amount can,however, be determined by preliminary tests.

While the invention has been described with particularity regardingcertain preferred embodiments thereof, it is obvious that variousmodifications and equivalents Will occur to those skilled in the art.Thus, it is intended, by the appended claims to cover such modificationsand equivalents insofar as the state of the art permits.

What is claimed is:

1. A cigarette comprising a tobacco element and a filter elementcomprising an insoluble polymeric N-vinyl lactam.

2. A cigarette comprising a tobacco element and a filter elementcomprising an insoluble polymeric N-vinyl pyrrolidone.

3. A cigar comprising a tobacco element and a filter element comprisingan insoluble polymeric N-vinyl lactam.

4. A cigar comprising a tobacco element and a filter element comprisingan insoluble polymeric N-Vinyl pyrrolidone.

5. A smoke-filter for tobacco smoke comprising a holder for the articleproducing said smoke, said holder containing an insoluble polymericN-vinyl lactam.

6. A smoke-filter for tobacco smoke comprising a holder for the articleproducing said smoke, said holder containing an insoluble polymericN-vinyl pyrrolidone.

7. A filter element for use in smoking devices comprising an insolublepolymeric N-vinyl lactam.

8. A filter element for use in smoking devices comprising an insolublepolymeric N-vinyl pyrrolidone.

References Cited UNITED STATES PATENTS 2,770,241 11/ 1956 Winkler 1.131208 2,792,006 5/1957 Marek 131-410 3,217,719 11/1965 Spears et al.131208 SAMUEL KOREN, Primary Examiner. D. J. DONOHUE, AssistantExaminer.

7. A FILTER ELEMENT FOR USE IN SMOKING DEVICES COMPRISING AN INSOLUBLEPOLYMERIC N-VINYL LACTAM.